<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        // 去除字符串内所有的空格：str = str.replace(/\s*/g,"");
        // var str = "北京你好 上海你好 长沙你好"
        // var str_1=str.replace(/\s*/g,"");
        // console.log(str_1);

        
    </script>
</body>
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